梅溪河大桥索塔锚固区三节段有限元分析

Finite Element Analysis of Three Segments in the Anchorage Zone of Meixihe Bridge

对在环向预应力单独作用、承载能力索力单独作用、承载能力极限状态和正常使用极限状态下的梅溪河大桥索塔锚固区上部三节段的有限元模型进行了计算与分析。结果表明,实桥模型齿块、预应力筋孔道及角隅等位置存在应力集中;实桥模型在环向预应力单独作用下与索力单独作用下位移方向相反;模型正常使用极限状态均为全截面偏心受压;齿块作为锚固和传力构件,对缓和斜拉索锚固的应力集中程度作用明显。这些结论对于斜拉桥索塔锚固区的设计和施工具有一定的指导意义。

The finite element model of the top three segments in the anchorage zone of Meixihe Bridge is calculated and analyzed when the circumferential pre-stress and the cable force of carrying ca- pacity are exerted alone and when the structure is in ultimate limit state and serviceability limit state. The results show that the stress concentration lies at the location of gear blocks, the tendon channels and the comers in the real bridge model; the displacement direction is contrary when the circumferential pre- stress and cable tension are exerted alone in the real bridge model; the model is eccentricity at the total cross section in serviceability limit state; as a force transmission and anchor components, the gear blocks can ease the degree of stress focus of cables in anchoring zone obviously. These conclusions have some guiding significances for the design and construction of anchorage zone in cable-stayed bridges.